JPH062150B2 - Base for patches - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved patch base.

The patch is to be applied to the skin for a long time and used. Therefore, as an indispensable condition for an ideal patch, it must satisfy the following various requirements.

1) The temperature resistance of the base material is excellent, and the base material is flexible regardless of summer or winter.

2) It must have sufficient water retention to keep the application site wet for a long time.

3) It should be an aqueous base that absorbs perspiration that causes a rash.

4) The pH of the aqueous base is neutral to weakly acidic with less skin irritation.

5) When the plaster is spread on the support, it should be spread evenly.

Conventionally, various aqueous bases have been proposed in order to meet such demands, and most of them have utilized the thermoplasticity of gelatin for shape retention and spreadability. For example, JP-A-57
JP-A-181020 discloses a gelatin-based pulp plaster composition characterized by containing an acrylic ester latex or a vinyl acetate-ethylene latex and a polyacrylate.

Although the gelatin-based base has good properties as a whole, it is easily affected by changes in temperature, softens when the temperature rises in the summer and causes an unpleasant stickiness when applied to the skin, or is temporary in the distribution process. There is a problem that discoloration and bleeding due to aging of the base material occur due to exposure to high temperature, and further, when the temperature decreases in winter, it hardens and lacks adhesiveness to the skin.

The present invention solves the problems of gelatin-based bases, and provides a base for patches, which can keep the adhesiveness to the skin constant regardless of the season and can satisfy all the above requirements. Is.

That is, the base of the present invention contains 5 to 40 polyhydric alcohol by weight.
Parts, sodium polyacrylate 1-10 parts, sodium carboxymethyl cellulose 1-10 parts, aluminum compound 0.01-30 parts, polyacrylic acid ester 1-10 parts, water 10
It is characterized by containing ~ 80 parts and adjusting the pH to 5 to 8 with an acid.

Gelatin is used as an important component for imparting spreadability to the base during the production of a patch due to its thermoplasticity and imparting shape retention to the produced patch. In a poultice containing a latex and a polyacrylic acid salt, it was considered that the presence of gelatin was indispensable like the pulp described in JP-A-57-181020.

According to the present invention, by blending the respective components in the ratios described above, the spreadability and shape retention which are not dependent on the thermoplasticity of gelatin are obtained, and a patch base having a stable tackiness throughout the four seasons is obtained. . Moreover, in the present invention, since gelatin is not used, there is no need to heat at 40 ° to 50 ° during the production, so that the advantage of eliminating the decrease in the content rate due to volatilization of the active ingredient can be obtained.

The shape retention of the base material in the present invention is mainly due to the crosslinking reaction between polyacryl-dispersed sodium and an aluminum compound in the presence of water, and the excellent shape retention at high temperature is largely different from the conventional gelatin base. Sodium polyacrylate having an average degree of polymerization of about 10,000 to 100,000 can be used, but particularly, an average degree of polymerization of about 15,000 to about 60,0.
00 is preferable.

Examples of aluminum compounds that can be used in the crosslinking reaction of sodium polyacrylate include activated alumina, synthetic aluminum silicate, aluminum hydroxide, kaolin and the like.

Cellulose derivatives such as sodium carboxymethyl cellulose are used to give a texture to the base due to its water retention and moisture retention properties, and to increase the tackiness when wet, which is one of the features of the base of the present invention. Addition to the above can eliminate the disadvantage of the conventional patch, that is, the decrease in the adhesive force at the time of sweating, and the decrease in the initial adhesive force due to the separation of the water content from the base.

The polyacrylic acid ester is added to the base material to maintain good initial tackiness when wet and long-term tackiness. As a polyacrylic acid ester that can be used, 2-ethylhexyl acrylate 85-
There are emulsion copolymers composed of 95 parts by weight and 5 to 15 parts by weight of methyl acrylate, or emulsion copolymers composed of 85 to 95 parts by weight of 2-ethylhexyl acrylate and 5 to 15 parts by weight of vinyl acetate.

Polyhydric alcohol is used as a base humidity control agent for the purpose of maintaining flexibility for a long time after use. Polyhydric alcohols that can be used include glycerin, sorbitol, propylene glycol, ethylene glycol and the like.

By adjusting the pH of the base to 5 to 8 with an acid, the active ingredients such as salicylic acid ester compounds are stably contained in the patch for a long time. Further, since the pH of the base is close to the pH of the skin surface, skin irritation that causes side effects such as rashes is reduced. The use of organic acids such as tartaric acid and citric acid is suitable for adjusting the pH.

It is important to use the amount of each of these components in the above proportions, and if it deviates from the range, good water retention, shape retention and cohesiveness of the base cannot be obtained.

The base of the present invention comprises, in addition to the above components, components conventionally used as a base for conventional patches, such as adhesives such as gum arabic, white inorganic pigments such as kaolin and titanium oxide, starch and sodium polyacrylate. A super absorbent polymer such as a copolymer, a surfactant such as polysorbate 80, and the like may be added as appropriate.

To produce a patch using the base of the present invention, the base of the present invention, for example, an essential oil component consisting of methyl salicylate,
Or other ingredients that can be expected to have a medicinal effect by percutaneous absorption are added, and the mixture is kneaded uniformly at a temperature of 10 to 30 ° C. (Thixotropic) is used to spread evenly on a support such as a cotton cloth or a non-woven cloth to a constant thickness, and the surface is covered with a plastic film.

Since the base of the present invention is composed of a synthetic polymer compound having almost no thermoplasticity, its adhesion to the skin surface is almost constant even if the temperature of the atmosphere changes, and its performance is almost the same even when stored for a long period of time. It does not change.

Furthermore, the base of the present invention has excellent temperature resistance and does not lose its cohesive strength due to aging of the base even when stored at a high temperature of around 60 ° for a long time.

In addition, since the cohesive force of the base material of the present invention is extremely stable, the liquid such as retained water does not exude from the back surface of the support at all. In addition, the base does not remain on the skin surface due to aging and loss of cohesive force. In this respect, the base of the present invention is completely different from the conventional product.

Next, the results of testing the properties of the poultice using the base of the present invention (hereinafter referred to as the poultice according to the present invention) in comparison with conventional products will be described. The compositions of the poultice according to the present invention and the conventional product used in the test are shown in Table 1 below.

For the adhesion test, a tester as shown in FIGS. 1 and 2 is used to place the adhesive surface of Sample 1, which is cut into a length of 10 cm on a slope of 30 ° with respect to the horizontal, facing upward. Upper part 7 cm and lower part 13 cm are cardboard 2 and 3 according to the sample thickness.
And fix them side by side. A steel ball with a diameter of 6.3 mm and a weight of 1.0 g is rolled from the upper end of the slope and the time it takes to reach the lower end of the central adhesive surface is measured and expressed as the adhesive force. At this time, the room temperature is 20 ° ± 1 °, and the adhesive surface of the sample and the steel ball must not be touched by hand. Also, once used steel balls are washed with warm water, dried, further washed with benzol and thoroughly dried before use.

Three types of samples are used, which have been stored in 5 °, 20 ° and 40 ° incubators for 24 hours. The test results are shown in Table 2 below.

In the severe test, immediately after production, the product was put in a bag made of aluminum foil, sealed, and stored in a 60 ° incubator for 3 weeks, and then observed for aging, discoloration, and bleeding. The results are shown in Table 3.

Next, examples of the present invention will be shown, but the present invention is not limited to these examples.

Example 1 2.5 parts of sodium polyacrylate, 3 parts of sodium carboxymethyl cellulose and 2 parts of methyl cellulose are dissolved in 30 parts of water. 0.5 part of tartaric acid is dissolved in 12.7 parts of water, 10 parts of glycerin, 10 parts of sorbitol and 20 parts of kaolin are added to prepare a suspension, which is then kneaded. Next, a suspension was prepared by adding 0.3 parts of activated alumina to 3 parts of polyacrylic acid ester and kneading the mixture uniformly to obtain a base.

Example 2 8 parts of sodium polyacrylate, 3 parts of sodium carboxymethyl cellulose and 1 part of a super absorbent resin are dissolved in 39 parts of water. Next, 10 parts of kaolin and 0.5 part of synthetic aluminum silicate suspended in 30 parts of glycerin are added and kneaded. Further, 2 parts of polyacrylic acid ester was added and uniformly kneaded to prepare a base.

Reference Example 1 4.6 parts of the following medicinal components and 0.4 part of a surfactant were added to 95 parts of the base material obtained in Example 1 or the base material obtained in Example 2 and uniformly kneaded before spreading on a support. Then, the drug surface is coated with a plastic film to give a poultice.

dl-camphor 1 part 1-menthol 1.5 parts methyl salicylate 2 parts diphenhydramine salicylate 0.1 part sorbitan sesquioleate 0.1 part polysorbate 80 0.3 parts As explained above, the base of the present invention consists of readily available ingredients Moreover, it not only has extremely excellent performance as a base, but is also less susceptible to temperature changes,
It is an excellent product that can maintain a certain quality for a long period of time.

[Brief description of drawings]

FIG. 1 shows a side view of the tester used for the adhesion test, and FIG. 2 shows a plan view of FIG. 1 ... Sample, 2 ... Upper cardboard, 3 ... Lower cardboard, 4 ... Steel ball, 5 ... Steel ball receiving box

Claims (1)

[Claims] 1. By weight, 5 to 40 parts of a polyhydric alcohol, 1 to 10 parts of sodium polyacrylate, 1 to 10 parts of sodium carboxymethyl cellulose, and an aluminum compound of 0.
A patch base comprising 01 to 30 parts, polyacrylic acid ester 1 to 10 parts, and water 10 to 80 parts, and adjusting the pH to 5 to 8 with an acid.